Another egregious security breach involving the Clinton Administration has occurred at the National Archives, this time the mysterious disappearance of a computer disc containing highly sensitive government files.

The disc containing national security information was lost sometime between October 2008 and March 2009 and its disappearance was finally made public this week by a lawmaker who sits on the House Oversight and Government Reform Committee. Federal authorities and Congress have launched a probe into the matter, which they had planned to keep private.

The missing disc contained Secret Service and White House operating procedures as well as other highly sensitive information from the Bill Clinton Administration. Among the files were 100,000 Social Security numbers, contact information for administration officials, detailed logs of events, political records and social gatherings. The full extent of the contents of the drive is still being investigated.

Security at the National Archives, which keeps official documents and materials of federal government business, has long been a joke. The archive inspector general has previously blasted its lack of internal controls, revealing that even the “secure” areas that house sensitive information are susceptible to breach.

This evidently allowed Clinton’s national security advisor, Sandy Berger, to remove highly classified terrorism documents from the archives as he prepared to testify before the September 11 Commission in 2003. Berger easily stole the files, hid them under a construction trailer and later tried to get a trash collector to retrieve them.

After initially denying he committed the crime, Berger pleaded guilty to unlawfully removing the classified files and got a tiny slap on the hand; a $50,000 fine, 100 hours of community service and a three-year ban from accessing classified material. The Justice Department subsequently determined that the full extent of what Berger took will never be known.